全文获取类型
收费全文 | 8571篇 |
免费 | 272篇 |
国内免费 | 1篇 |
专业分类
管理学 | 1383篇 |
民族学 | 69篇 |
人才学 | 1篇 |
人口学 | 773篇 |
丛书文集 | 70篇 |
教育普及 | 1篇 |
理论方法论 | 857篇 |
综合类 | 221篇 |
社会学 | 4016篇 |
统计学 | 1453篇 |
出版年
2023年 | 50篇 |
2021年 | 62篇 |
2020年 | 124篇 |
2019年 | 171篇 |
2018年 | 198篇 |
2017年 | 269篇 |
2016年 | 216篇 |
2015年 | 133篇 |
2014年 | 219篇 |
2013年 | 1317篇 |
2012年 | 282篇 |
2011年 | 277篇 |
2010年 | 214篇 |
2009年 | 203篇 |
2008年 | 259篇 |
2007年 | 240篇 |
2006年 | 267篇 |
2005年 | 216篇 |
2004年 | 267篇 |
2003年 | 188篇 |
2002年 | 224篇 |
2001年 | 223篇 |
2000年 | 278篇 |
1999年 | 207篇 |
1998年 | 158篇 |
1997年 | 145篇 |
1996年 | 161篇 |
1995年 | 108篇 |
1994年 | 107篇 |
1993年 | 132篇 |
1992年 | 133篇 |
1991年 | 144篇 |
1990年 | 119篇 |
1989年 | 111篇 |
1988年 | 92篇 |
1987年 | 96篇 |
1986年 | 81篇 |
1985年 | 100篇 |
1984年 | 107篇 |
1983年 | 108篇 |
1982年 | 79篇 |
1981年 | 86篇 |
1980年 | 68篇 |
1979年 | 71篇 |
1978年 | 59篇 |
1977年 | 61篇 |
1976年 | 61篇 |
1975年 | 49篇 |
1974年 | 51篇 |
1973年 | 50篇 |
排序方式: 共有8844条查询结果,搜索用时 31 毫秒
81.
82.
83.
Regina Thompson Paul H. Templet John K. Gamman Scott T. McCleary Margaret A. Reams 《Risk analysis》1994,14(5):857-861
The goal of Louisiana's 1990–1991 comparative risk project, also called the Louisiana Environmental Action Plan (LEAP), was to incorporate risk assessment into state environmental planning and policymaking. Scientists, government officials, and citizens were brought together to estimate the relative risk to human health, natural resources, and quality of life posed by 33 selected environmental issues. The issues were then ranked according to their relative estimated risks. It was hoped that this ranking of "comparative risks" would enable state policymakers to target the most important environmental problems and allocate scarce public resources more rationally and efficiently. As a result of the project, the governor issued an Executive Order forming a permanent Public Advisory Committee to continue this type of comparative risk assessment in Louisiana. 相似文献
84.
Abstract The objective of this study is to examine female labor force participation and its determinants in rural and urban China. The sociological literature has demonstrated that participation tends to increase in urban and industrialized places where women have higher levels of education and fewer children, where more workers are engaged in service pursuits, and where family structure is less traditional. With the use of data on counties and cities (N = 2,377) from the I-percent sample of the 1982 census of the People's Republic of China, it was found that female labor force participation is likely to rise in areas with increased agricultural employment, educational levels, proportion of female-headed households, and higher male-to-female sex ratios. Both the size of the service sector and the fertility rate had negligible effects on female labor force participation. Although, on average, rural places have slightly higher levels of female labor force participation, when other variables are controlled, urban places have a higher rate of female participation. In addition, the findings suggest that market factors (i.e., education) are more likely to determine the rate of female labor force participation in urban areas; whereas demographic and social factors (i.e., sex ratio and household structure) play a more important role in explaining the female labor force participation in rural counties. 相似文献
85.
T J Young 《Journal of drug education》1991,21(1):65-72
Although Native Americans are plagued by high rates of alcoholism, violence, suicide and early death, these social and clinical problems are usually given little more than cursory treatment in textbooks. A content analysis of twenty-six textbooks on alcoholism and substance misuse revealed that only four provided a detailed discussion of Native American drinking. Greater attention needs to be given to the cultural, psychological, and biological issues of drinking and drunkenness among this special population. 相似文献
86.
The EM algorithm is a popular method for maximizing a likelihood in the presence of incomplete data. When the likelihood has multiple local maxima, the parameter space can be partitioned into domains of convergence, one for each local maximum. In this paper we investigate these domains for the location family generated by the t-distribution. We show that, perhaps somewhat surprisingly, these domains need not be connected sets. As an extreme case we give an example of a domain which consists of an infinite union of disjoint open intervals. Thus the convergence behaviour of the EM algorithm can be quite sensitive to the starting point. 相似文献
87.
88.
The present study was conducted to assess differences in the behavioral and demographic characteristics of snuff (dip) users as compared to users of chewing tobacco. High School football players (1116) were surveyed concerning their use and perceptions of smokeless tobacco. Adolescent athletes who tried smokeless tobacco were more likely to be white, to use cigarettes, alcohol, and cigars and to have family users than those who never tried. Initial use was highest before the age of fourteen years and was influenced by friends, curiosity and family. Dippers tended to initiate use because of friends, while chewers started because of family users. Users of both dip and chew started primarily because of curiosity. Users of both were more likely to consume greater amounts to alcohol and cigarettes and to smoke cigars and pipes. It appears that the longer smokeless tobacco is consumed, the more likely both dip and chew will be used. Users of smokeless tobacco for more than two years tended to consume more of the product each week, used it for more hours/day, initiated use at an earlier age, and used it more often at school and work than those using it for less than two years. Use of cigars/pipes, consumption of alcohol, and quantity of cigarette consumption increased significantly with longer duration of smokeless tobacco use. Intervention and prevention programs would be helped by understanding differences between users of various smokeless tobacco products and differences related to the duration of use. In addition, further analyses of smokeless tobacco users should study chewers, dippers, and users of both separately. 相似文献
89.
J. Richard Udry 《Demography》1994,31(4):561-573
I explain a biosocial model of women’s gendered behavior (behavior on which the sexes differ). This model integrates a macro sociological theory with a biological theory derived from primate behavior. The sociological model is designed to explain changes in the relationship between sex and behavior over time or between groups. The biological model is designed to explain individual within-sex variance and between-sex variance in gendered behavior in a cohort. Results from an original study are presented to demonstrate that within-sex variance in women’s gendered behavior is explained well by the primate model. I conclude that human nature is gendered. The implications of this conclusion are explored for demographic and other social science research. 相似文献
90.